Safety device for elevators.



A W AGKERMAN SAFETY DEVICE FOR ELEVATORS. APPLICATION FILED 0012.5,1908. 934,645, Patented Sept. 21, 1909. a sums-sum 1. Q N

A. W. AUKERMAN. SAFETY DEVICE FOR ELEVATORS.

APPLICATION FILED 00m, 1908.

934,645, Patented Sept. 21, 1909.

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A. 'W. AGKERMAN.

SAFETY DEVICE FOR ELEVATORS, APPLICATION FILED 0012.5, 1908.

934,645. Patented Sept. 21, 1909.

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UNITED srnrns 1 PATENT onnion.

ALBERT W. ACKERMAN, F FALKS STORE, IDAHO, ASSIGNOR OF ONE-TENTH TO J.HERBERT THOMPSON, OF NEW PLYMOUTH, IDAHO.

SAFETY DEVICE FOR ELEVATORS.

Application filed October 5, 1908.

To all whom it may concern:

Be it known that I, ALBERT W. AGKERMAN, a citizen of the United States,residing at Falks Store, in the county of Canyon, State of Idaho, haveinvented certain new and useful Improvements in Safety Devices forElevators; and I do hereby declare the following to be a full, clear,and exact description of the invention, such as will enableothersskilled in the art to which it appertains to make and use the same.

The invention relates to a safety device for elevators and moreparticularly to the class of automatic safety devices for elevator cagesto prevent the same from dropping should the lifting cable become brokenor detached therefrom.

The primary object of the invention is the provision of a safety devicefor elevators such as mining or other cages which device willautomatically operate to arrest or prevent the downward flight or dropof the cage should the lifting cable thereof become broken or detachedfrom the cage.

Another object of the invention is the provision of a safety device forelevators, mine cages or the like comprising catcher members adapted tobe automatically operated upon the breaking or detachment of the liftingcable to engage the walls of the well between which the elevator or cagetravels, so as to prevent the latter from dropping upon the breaking ordetachment of the said lifting cable thereof.

A further object of the invention is the provision of a safety deviceautomatically actuated to arrest an elevator cage upon the breaking ofits lifting cable or the detachment of the cable from the cage and meansto prevent the automatic action of the safety device when the liftingcable becomes slack upon the arrival of the cage at the lowest point ofdescent within the elevator well in which the cage vertically travels.

In the drawings accompanying and forming part of this specification isillustrated the preferred form of embodiment of the invention, which, toenable those skilled in the art to practice the invention, will be setforth at length in the following description, while the novelty of theinvention will be included in the claims succeeding the description.

In the drawings :Figure 1 is a front elevation of an elevator cage andwell and the Specification of Letters Patent.

Patented Sept. 21, 1909.

Serial No. 456,183.

invention applied thereto. Fig. 2 is a vertical sectional view takenthrough the upper portion of the elevator cage and the well in which thesame travels, with the invention applied to the cage and partly insection. Fig. 3 is a'vertical sectional view through the safety deviceand showing the same in an inoperative position. Fig. 4; is a similarview with the same in an operative position for arresting the elevatorcage. Fig. 5 is a transverse sectional view on the line 55 of Fig. 1.Fig. 6 is a top plan view of the elevator cage with the safety device inposition thereon.

Similar reference characters indicate corresponding parts throughout theseveral views in the drawings.

In the drawings the numeral 10 designates the elevator cage which is ofthe usual construction and is adapted to travel vertically in a well 11,the latter also being of the usual or ordinary construction and risingfrom the top of said cage 10 are bail irons 12, the lower ends of whichare connected at opposite points of the cage and converge inwardlytoward each other, while the upper ends thereof are fixed to the lowerextremities of spaced vertical side walls 13 of a housing or casing lt,the latter having a perforated cross head 15, through which passes alifting cable 16, the same having its lower end connected to an eye 17of a stem fixed centrally in a weighted block 18, which latter ismounted for sliding movement between the side walls 13 within thehousing or casing.

Centrally of the housing or casing 1 1 and connected to the side walls13 thereof is a transverse partition plate 19, dividing the said housingand easing into upper and lower spaces, the space below the partitionplate having mounted therein a slidable plunger head or block 20 havingformed in one side thereof a notch 21 and in its opposite side aplurality of rack teeth 22 and pivotally mounted in the lower end of thesaid plunger head or block 20 are catcher arms 23, which latter areadapted to move outwardly at opposite sides of the cage 10 and engage inthe side walls of the well 11, to arrest the said cage for preventingthe dropping thereof when the lifting cable 16 becomes broken ordetached from the same. Connected to the underface of the weighted block18 and to the transverse plate 19 are of the well.

retractile springs 18 which latter serve to lower the said block 18 uponthe breaking of the lifting cable 16 so that the weighted block willactuate the locking dogs hereinafter described.

Joined to the bail irons 12 is a bridge piece 2 1, the same having guideopenings 25 through which pass the catcher arms 23 and which bridgepiece serves to spread the said arms outwardly to engage the side wallsMounted upon the lower end of the plunger head or block 20 and dependingtherefrom is a clevis 26 to which is connected one end of a retractilespring 27, the opposite end of which is connected centrally to thebridge piece 24, the spring acting to bring the catcher arms 23 inposition for engagement with the side walls of the well upon thebreaking of the lifting cable 16 connected to the elevator cage.

Projecting from the side walls 13 of the housing or casing 14- arespaced ears 28 between which are pivoted locking dogs 29 and 30, thelatter normally in locked engagement with the notch 21 in the plungerhead or block 20 to hold the same against the tension of the retractilespring 27 and to maintain the catcher arms 23 in an inoperativeposition, while the locking dog 29 is normally held out of engagementwith the rack teeth 22 of said plunger head or block 20, however, upondisengagement of the locking dog 30 from the notch 21 of said plungerhead or block 20, and when the latter lowers upon the action of theretractile spring 2", the said locking dog 29 will automatically engagethe rack teeth 22 to lock the said plunger head or block against reversemovement and maintain the catcher arms 23 in engagement with the wallsof the well to hold the cage against movement or arrest the same fromdropping in said well. The said locking dog 30 has an inwardly curvedextension 31 terminating in the path of movement of the weighted block18 above the partition plate 19 and which extension is pivotallyconnected to a forked arm 32, the latter having a downwardly curvedextremity 33 loosely engaging a loop 34 formed on the upper end of thevertical extension 35 of the locking dog 29, so that when the liftingcable 16 becomes detached or broken the weighted block 18 under theinfluence of the springs 18 will drop and act upon the extension 31 andforked arm 32 so as to disengage the locking dog 30 from the plungerhead or block 20 which latter will automatically shift the catcher arms23 into engagement with the walls of the well 11 to arrest the cage orprevent the same from dropping in the well. The said plunger head orblock 20 has formed centrally therein a vertical elongated slot 36 inwhich is mounted a transverse friction roller 37, the latter rotatablymounted upon a bolt or pin 38 uniting the lower end of spaced parallelstrips 39, the upper ends of which are fixed to opposite sides of theweighted block 18 and serve to guide the latter in its downward movementupon the breaking of the lifting cable or detachment thereof from thecage.

Rising from the partition plate 19 is an expansion spring 40, the latterconnected to the pivotal connection uniting the extension 31 and forkedarm 32 which spring serves to normally hold the locking dog 30 inengagement with the notch in the plunger head or block. Secured to theopposite side walls 13 of the housing or casing are the inner ends of anexpansion spring ll and a retractile spring 41, the outer ends of whichare connected to the extension 31 and extension 35 of the locking dogsrespectively to reset the same after having been acted upon by theweighted block 18 when the lifting cable 16 has been detached or brokenfrom the elevator cage.

Should the lifting cable become broken or detached and there be dangerof the cage falling, the weighted and spring actuated block 18 will fallinto engagement with the extension 31 arranged in the path of movementthereof to release the locking dog 30 to free the plunger head or block20 which latter will move downwardly in the housing or casing, thusforcing the lower ends of the catcher arms 23 outwardly and the endsthereof will engage the walls of the well 11 thus automatically andinstantly arresting or stopping the cage in its descent within the well.

It is to be understood that changes, variations and modifications may bemade in the construction of this invention such as come properly withinthe scope of the claims here unto appended without departing from thespirit of the invention.

The safety device is simple in construction, )ositive in action can beapplied to any elevator wherein the cage is suspended by a cable and isvery effective in preventing the elevator cages from falling, andresulting accidents.

\Vhat is claimed is 1. In a safety device of theclass described, thecombination with an elevator cage and its lifting cable, of a housingrising from the top of said cage, a plunger block slidably mounted inthe housing, otally connected to the plunger block and movable from aninoperative to an operative position by the latter, means for lockingthe plunger block against'movement, means operative upon the breaking ofthe lifting cable of the cage for releasing said locking means to freethe plunger block and means for locking the plunger block againstreverse movement.

2. In a safety device of the class described,

catcher arms piv-' the combination with an elevator cage and slidablymounted in the housing, catcher arms connected to said plunger block andadapted to be moved to an operative position thereby, weighted meansslidably mounted within the housing and having connection with thelifting cable of the cage, locking means arranged in the path ofmovement of the weighted means and normally holding the plunger blockagainst movement and adapted to free the same when operated upon by theweighted means and means cooperative with the locking means to preventback movement of the plunger block.

3. The combination with an elevator age and its well in which the sametravels, of a lifting cable for the cage, a housing mounted upon saidcage, a plunger head slidable in the housing, catcher arms pivotallyconnected to the plun er head, locking dogs, one of which normallyholding said plunger head against movement and means operative upon thebreaking of the lifting cable sup porting the cage to actuate thelocking dogs for freeing the plunger head and preventing back movementthereof.

at. In a safety device, the combination with an elevator cage and itslifting cable, of *atcher arms supported by said cage, a sliding plungerhead having connection with the catcher arms, locking means normallyholding the plunger head against movement to maintain the catcher armsin an operative position, means operative upon the locking means to freethe sliding plunger head upon the breaking of the lifting cablesupporting the cage and means controlled by the last mentioned means toprevent reverse sliding movement of the plunger head after the same hasbeen freed.

5. In a safety device the combination with an elevator cage and itslifting cable, of bail irons rising from the top of the latter, ahousing connected to the bail irons, a plunger element slidably mountedin the housing, catcher means controlled by said plunger element, springset locking dogs mounted upon said housing, one of said dogs normallylocking the plunger element against movement, a slidable weight arrangedwithin the housing above the plunger element and operative upon thebreaking of the lifting cable sup porting the cage to actuate one of thedogs to free the plunger element and also to operate the other dog tobring the same into position to engage the plunger head and preventreverse sliding movement thereof and spring means acting upon theplunger element when freed to bring the catcher means in an operativeposition.

In testimony whereof, I affix my signature, in presence of twoWitnesses.

ALBERT AOKERMAN.

Witnesses FRED FAIRMAN, GEO. AGKERMAN.

